Composition comprising a diindolylmethane and a retinoid to treat a skin condition

ABSTRACT

Provided is a composition for use in treating a skin condition, the composition comprising: (a) a first component comprising a substituted or unsubstituted diindolylmethane compound; and (b) a second component comprising a substituted or unsubstituted retinoid compound.

The present application concerns a pharmaceutical composition or kit comprising a diindolylmethane (DIM) compound for use in treating a skin condition, such as acne. The composition comprises a further component in addition to the DIM in order to enhance the pharmaceutical effect of the DIM.

DIM compounds have been known for some time as pharmaceutically active agents. In particular, naturally occurring DIM has been shown to be a useful treatment for the Human Papilloma Virus (HPV). WO 03/034992 discloses the use of DIM in the treatment of verrucae and warts, conditions caused by infection with HPV. The DIM is employed either alone, or in combination with immune potentiating steroids.

DIM has also been used to treat certain other skin conditions, as well as a wide variety of other diseases. US 2005/0058600 A describes the use of DIM for the treatment of acne, alopecia, hirsuitism and even prostate cancer. It is particularly preferred that the DIM is combined with other anti-androgenics, such as bicalutamide, cyproterone, finasteride, dutasteride, ketoconazole, nilutamide, and spironolactone. The paper by Kim et al. in Molecular Carcinogenesis (vol. 49, pp. 672-683, 2010) discloses that DIM may be used to treat tumours in mice. CN 101428016 A discloses that DIM may be useful in treating acne, rheumatoid arthritis and cancer. WO 2009/103754 discloses the use of DIM to treat signs of aging. It also discloses that other additives may be employed, such as vitamin B, for improving nutrition. However, it is still necessary to improve the activity and effectiveness of DIM treatment, especially in relation to skin conditions.

DIM has also found use in combination with vitamin A in treating a number of further diseases. For example, WO 05/089412 discloses the use of DIM in combination with vitamin A for the treatment of cancer. WO 07/096886 discloses the use of DIM and vitamin A for treating eye diseases. WO 06/083458 discloses a similar combination for treating respiratory diseases. WO 06/047716 discloses another similar combination for treating human cytomegalovirus.

The present inventors have been concerned with improving the treatment of skin conditions for some time, and have taken a particular interest in acne, inflammation and signs of aging. Although DIM has found use in treating a number of conditions, as discussed above, to date its use in treating skin conditions, such as those of interest to the inventors, has not been as effective as is desired. However, in the two aspects of the invention the inventors have surprisingly discovered that DIM, when combined with certain carefully selected synergistic components, has significant efficacy in treating and preventing such skin conditions. The inventors were also concerned with reducing side effects from known treatments, and have found that the surprising combinations of each aspect of the invention have improved side effect profiles as compared with known treatments.

Accordingly, in a first aspect the present invention provides a composition for use in treating a skin condition, the composition comprising:

-   -   (a) a first component comprising a substituted or unsubstituted         diindolylmethane compound; and     -   (b) a second component comprising a substituted or unsubstituted         retinoid compound.

The inventors have discovered in particular that surprisingly DIM, when combined with the above selected synergistic second component, has significant efficacy in treating and preventing acne, inflammation, and/or the effects of aging in skin.

The invention further provides a pharmaceutical kit for separate, simultaneous or sequential administration for use in treating a skin condition, which kit comprises a first component and a second component, wherein the first and second components are as defined above.

The composition of the present invention, either in composition or in kit form, has been shown in clinical trials to have significant advantages over known treatments. The results of the trials will be discussed in more detail in the Examples.

The invention will now be explained in more detail by way of example only, with reference to the following Figures:

FIG. 1 shows a patient from Group A with Acne vulgaris prior to treatment with a composition of the present invention comprising BioResponse DIM and vitamin A.

FIG. 2 shows the patient from FIG. 1 after treatment with a composition of the present invention comprising BioResponse DIM and vitamin A.

FIG. 3 shows a patient from Group B with Acne vulgaris prior to treatment with a composition of the present invention comprising BioResponse DIM and vitamin A.

FIG. 4 shows the patient from FIG. 3 after treatment with a composition of the present invention comprising BioResponse DIM and vitamin A.

The components of the composition will now be explained in further detail.

As mentioned above, the first component comprises a diindolylmethane (DIM) compound. The first component is not especially limited provided that it comprises a DIM compound, and thus may also comprise one or more further DIM compounds of the type described below.

The DIM compound may be any compound comprising a diindolylmethane group, but is preferably a compound having the following structure:

wherein the R groups may be the same or different substituents. The substituents are not particularly limited and may comprise any organic group and/or one or more atoms from any of groups IIIA, IVA, VA, VIA or VIIA of the Periodic Table, such as a B, Si, N, P, O, or S atom or a halogen atom (e.g. F, Cl, Br or I).

When the substituent comprises an organic group, the organic group preferably comprises a hydrocarbon group. The hydrocarbon group may comprise a straight chain, a branched chain or a cyclic group. Independently, the hydrocarbon group may comprise an aliphatic or an aromatic group. Also independently, the hydrocarbon group may comprise a saturated or unsaturated group.

When the hydrocarbon comprises an unsaturated group, it may comprise one or more alkene functionalities and/or one or more alkyne functionalities. When the hydrocarbon comprises a straight or branched chain group, it may comprise one or more primary, secondary and/or tertiary alkyl groups. When the hydrocarbon comprises a cyclic group it may comprise an aromatic ring, an aliphatic ring, a heterocyclic group, and/or fused ring derivatives of these groups. The cyclic group may thus comprise a benzene, naphthalene, anthracene, indene, fluorene, pyridine, quinoline, thiophene, benzothiophene, furan, benzofuran, pyrrole, indole, imidazole, thiazole, and/or an oxazole group, as well as regioisomers of the above groups.

The number of carbon atoms in the hydrocarbon group is not especially limited, but preferably the hydrocarbon group comprises from 1-40 C atoms. The hydrocarbon group may thus be a lower hydrocarbon (1-6 C atoms) or a higher hydrocarbon (7 C atoms or more, e.g. 7-40 C atoms). The number of atoms in the ring of the cyclic group is not especially limited, but preferably the ring of the cyclic group comprises from 3-10 atoms, such as 3, 4, 5, 6 or 7 atoms.

The groups comprising heteroatoms described above, as well as any of the other groups defined above, may comprise one or more heteroatoms from any of groups IIIA, IVA, VA, VIA or VIIA of the Periodic Table, such as a B, Si, N, P, O, or S atom or a halogen atom (e.g. F, Cl, Br or I). Thus the substituent may comprise one or more of any of the common functional groups in organic chemistry, such as hydroxy groups, carboxylic acid groups, ester groups, ether groups, aldehyde groups, ketone groups, amine groups, amide groups, imine groups, thiol groups, thioether groups, sulphate groups, sulphonic acid groups, and phosphate groups etc. The substituent may also comprise derivatives of these groups, such as carboxylic acid anhydrydes and carboxylic acid halides.

In addition, any substituent may comprise a combination of two or more of the substituents and/or functional groups defined above.

Preferably the substituents are selected from hydrogen atoms and C₁-C₆ hydrocarbon substituents such as C₁-C₆ alkyl groups (e.g. methyl, ethyl, propyl, isopropyl, and butyl groups). Most preferably both R substituents are hydrogen atoms.

The indolyl groups in the above formula are not especially limited and may be the same or different. Preferably they are both indole-3-yl groups, but alternatively both may indole-2-yl groups or one may be indole-3-yl and the other indole-2-yl. The indolyl groups may have the same or different substituents and may be unsubstituted such that all substituents are hydrogen atoms, or may be substituted with one or more of any of the substituents defined above. Preferably the substituents are selected from hydrogen atoms and C₁-C₆ hydrocarbon substituents such as C₁-C₆ alkyl groups (e.g. methyl, ethyl, propyl, isopropyl, and butyl groups). Most preferably all substituents are hydrogen atoms, i.e. the indolyl groups are unsubstituted.

Typically, but not exclusively, the first component comprises a substituted or unsubstituted 3,3′diindolylmethane compound and/or a substituted or unsubstituted 2,2′diindolylmethane compound selected from the following structures:

wherein the R groups may be the same or different and are selected from hydrogen atoms, or from C₁-C₆ hydrocarbon substituents.

More preferably the first component comprises a 3,3′diindolylmethane compound and/or a 2,2′diindolylmethane compound selected from the following structures:

As has been mentioned above, the compositions and kits of the present invention comprise a second component comprising a substituted or unsubstituted retinoid compound. The second component typically has a beneficial effect supplementary to and/or complementary to the effect of the first component. In the present context, the effect of the second component may thus be complementary to that of the first component (i.e. its effect may differ from that of the first component, but be additionally beneficial for treatment of the skin condition in question) or may be supplementary to the effect of the first component (i.e. it may have the same effect as the first component, producing an additive effect or enhancing the pharmaceutical effect of the first component). Components that have a synergistic effect or any other beneficial relationship with the first component are thus intended to be encompassed by this definition.

The composition may also comprise one or more further components. The further components are not especially limited, and typically provide a beneficial effect as explained above. In some embodiments the further components are selected from one or more of: a further substituted or unsubstituted retinoid compound, an antibiotic compound, a substituted or unsubstituted azelaic acid compound, an oral contraceptive compound, sulphur, a sulphur-containing compound, a substituted or unsubstituted salicylic acid compound, a substituted or unsubstituted resorcinol compound, a plant product, a mineral, a vitamin (typically not vitamin A which instead may be present as a retinoid compound), and a neutraceutical product.

The further component may comprise either one such compound described above or two or more of these compounds, depending upon the requirements of the formulation.

The retinoid compound of the second component is not especially limited, and may be any such compound known in the art that is suitable for use with the skin. For example, it may be selected from a substituted or unsubstituted first generation retinoid, a substituted or unsubstituted second generation retinoid and a substituted or unsubstituted third generation retinoid. More preferably the retinoid is a substituted or unsubstituted first generation retinoid. Typically, the first generation retinoid is selected from a substituted or unsubstituted retinol, a substituted or unsubstituted retinal, a substituted or unsubstituted tretinoin (e.g. retinoic acid or Retin A), a substituted or unsubstituted isotretinoin (e.g. Accutane™), and a substituted or unsubstituted alitretinoin. Most preferably the retinoid comprises vitamin A. When the retinoid is a second generation retinoid, it is typically selected from a substituted or unsubstituted etretinate, and a substituted or unsubstituted acitretin. When the retinoid is a third generation retinoid, it is typically selected from a substituted or unsubstituted tazarotene, a substituted or unsubstituted bexarotene, and a substituted or unsubstituted adapalene.

When the further component comprises an antibiotic compound, the antibiotic compound is not especially limited, and may be any such compound known in the art that is suitable for use with the skin. Typically the antibiotic compound is suitable for oral and/ortopical application and is selected from: tetracycline, oxytetracycline, minocycline, doxycycline, erythromycin and trimethoprim.

When the further component comprises an azelaic acid compound, the azelaic acid compound is not especially limited, and may be any such compound known in the art that is suitable for use with the skin. Typically the azelaic acid compound comprises an antibacterial and/or an anti-inflammatory property.

When the further component comprises an oral contraceptive compound, the oral contraceptive compound is not especially limited, and may be any such compound known in the art that is suitable for use with the skin. Typically the oral contraceptive comprises a female hormone and/or a compound with female hormone activity, capable of counteracting the effect of a male hormone. In some embodiments, the female hormone is oestrogen and the male hormone is testosterone.

When the further component comprises sulphur, or a sulphur-containing compound, the sulphur or sulphur-containing compound is not especially limited, and may be any such compound known in the art that is suitable for use with the skin. Typically the sulphur or sulphur-containing compound comprises sulphur either alone or in combination with other substances such as alcohol, salicylic acid and/or resorcinol.

When the further component comprises a resorcinol compound, the resorcinol compound is not especially limited, and may be any such compound known in the art that is suitable for use with the skin. Typically the resorcinol compound comprises an antibacterial and/or an anti-inflammatory property.

When the further component comprises a plant product, it typically but not exclusively comprises an extract from one or more of the following:

-   -   Urtica dioica (stinging nettle)—has significant         anti-inflammatory effects helping to reduce the redness and         swelling in acne     -   Ribes nigrum (blackcurrant)—has significant anti-inflammatory         and antioxidant properties     -   Echinacea purpurea and/or Echinacea angustifolia—contain active         substances that enhance the activity of the immune system,         reduce inflammation and antioxidant effects     -   Cnidium monnieri—acts through its antibacterial, antifungal, and         astringent properties     -   Berberis aquafolium (Oregon grape)—may decrease sebum         production, and reduce infection and inflammation     -   Chamomile Matricaria (German chamomile)—has antibacterial         properties and inactivates bacterial toxins. May reduce         inflammation, and speed wound healing     -   Phytolacca decandra (poke root)     -   Cruciferous vegetables—synergistic effects may be achieved by         the addition of extracts, concentrates and processed extracts of         cruciferous vegetables such as broccoli, sprouts etc. These may         provide active products with significant added antioxidant and         anti-inflammatory effects.

When the further component comprises a mineral, it typically but not exclusively comprises one or more of:

-   -   Zinc—may promote reduction of inflammation and healing of         damaged skin     -   Chromium—may help boost the body's ability to break down glucose     -   Selenium—may help to balance decreased levels of antioxidant         enzymes and may reduce persistent acne and help lessen the         appearance of scars

When the further component comprises a vitamin, it typically but not exclusively comprises one or more of:

-   -   Vitamin B complex—combinations of B vitamins B1, B2, B3, B4, B5,         B6, B7, B9 and B12—may balance the metabolism of hormones, which         have a significant role in the condition of Acne     -   Vitamin C—a highly effective antioxidant, which stimulates         tissue growth and repair. May contribute to the acne healing         process     -   Vitamin E—a potent antioxidant

When the further component comprises a further neutraceutical product, it comprises a product that has some further nutritional or pharmaceutical property that is complementary or supplementary to the effect of the first and/or second component. Typically but not exclusively further neutraceutical products may be selected from one or more of:

-   -   Evening primrose oil—contains fatty acids, which may help         decrease inflammation related to skin conditions     -   Plant isoflavones—from foods including soy bean and red         clover—have significant natural antioxidant properties and a         balancing effect on estrogenic hormones     -   Turmeric—has anti-inflammatory properties from the primary         active component curcumin     -   Omega 3 oils—long-chain n-3 fatty acids may have         anti-inflammatory activity

The compound of the second (and/or further) component may be substituted or unsubstituted. When the compounds are substituted, they may be substituted with any of the substituents defined above. Preferably the substituents are selected from hydrogen atoms and C₁-C₆ hydrocarbon substituents such as C₁-C₆ alkyl groups (e.g. methyl, ethyl, propyl, isopropyl, and butyl groups). Most preferably all substituents are hydrogen atoms, i.e. the compounds are unsubstituted.

A particularly advantageous embodiment of the invention is a composition or kit in which the first component comprises unsubstituted 3,3′diindolylmethane and the second component comprises a vitamin A compound (e.g. vitamin A palmitate). Further advantageous additive and excipient compounds for inclusion in such advantageous embodiments include one or more of vitamin E, vitamin C, phosphatidyl choline, microcrystalline cellulose (plant fibre), magnesium stearate and silica (further explanation on additives and excipients is provided below).

The skin condition that the present compositions and kits may be used for treating is not especially limited, but is typically selected from acne, skin inflammation and skin aging effects (such as wrinkles and other age-related blemishes). In the more preferred embodiments of the invention, the acne comprises acne vulgaris, seborrhoea, comedones, papules, pustules, nodules, cysts, boils and/or scarring.

The formulation of the composition (and the kit components) use in the present invention is not especially limited, and any formulation suitable for administration to a human or other subject may be used. However, typically the composition (and the kit components) are formulated for oral or topical administration. Thus, the composition (and the kit components) may be provided in the form of a tablet, capsule, gel, cream or ointment.

Further explanation will now be given on the bioavailability of the DIM component. Diindolylmethane (DIM) is a natural compound formed during the autolytic breakdown of glucobrassicin present in food plants of the Brassica genus, including broccoli, cabbage, Brussels sprouts, cauliflower and kale. The autolytic breakdown of glucobrassicin requires the catalytic reaction of the enzyme myrosinase, which is endogenous to these plants and released upon rupture of the cell wall. The compound is normally manufactured by chemical synthesis but may also be prepared by natural means from the extracts of Brassica vegetables, as listed above, particularly from sprouting broccoli or from broccoli seeds. As has been mentioned, any DIM compound, or combination of DIM compounds may be employed in the invention. Thus, the DIM compound may be synthetic, or may be a natural product obtained from a Brassica plant, as discussed above.

Typically however, the diindolylmethane compound is adapted for increased bioavailability, in order to reduce the required dosage. One such useful DIM with increased bioavailability is BioResponse Diindolylmethane (from BioResponse LLC).

The dosage of the DIM component is not especially limited, provided that it is sufficiently low to avoid toxicity, whilst still maintaining the required pharmaceutical effect. The dosage may depend on the bioavailability of the DIM, which may vary depending upon whether it is a natural or synthetic product, and on whether it has been adapted to improve bioavailability. Typically the first component is in a form suitable for providing a daily DIM dosage of 500 mg or less, preferably from 10-500 mg. Most preferably about 150 mg or about 350 mg. The higher dosages are preferred for DIM that has not been adapted to improve bioavailability. More preferably the first component is in a form suitable for providing a daily DIM dosage of 15-100 mg, preferably 18-75 mg. The lower dosages are preferred for DIM that has been adapted to improve bioavailability.

The dosage of the substituted or unsubstituted retinoid compound component is not especially limited, provided that it is sufficiently low to avoid toxicity, whilst still maintaining the required pharmaceutical effect. The dosage may depend on the bioavailability of the retinoid compound, which may vary depending upon whether it is a natural or synthetic product, and on whether it has been adapted to improve bioavailability. Typically the second component is in a form suitable for providing a daily dosage of 5000 μg or less, preferably 3000 μg or less, preferably 50 μg or more, 100 μg or more, or 200 μg or more, and more preferably still from 200-3000 μg.

In the more typical embodiments, the daily dosage is provided in the form of one or more capsules or tablets, preferably in the form of 2 or 4 capsules or tablets. In these embodiments the capsules or tablets are designed to be taken during the course of a single day, such as one in the morning and one in the evening, or four spread evenly across the day, or two tablets simultaneously twice a day.

The first component and/or the second component in the compositions and kits may comprise one or more further additives, excipients and/or adjuvants. These additives, excipients and adjuvants are not especially limited, provided that they enhance the effectiveness of the first and/or second components, or are advantageous in forming a working formulation for the pharmaceutical. Diindolylmethane is a lipophilic oil-soluble compound. Similar to other oil soluble phytochemicals, the presence of oil and other lipophilic compounds, such as phosphatidylcholine and vitamin E, greatly increases the absorption and bioavailability of DIM upon oral administration. Thus, the first component typically comprises one or more further oil-soluble and/or lipophilic compounds, such as vitamin E and/or phosphatidylcholine. Further advantageous additives may also be added to the first and/or the second component. These include, but are not limited to, microcrystalline cellulose (plant fibre), magnesium stearate and silica.

The invention further provides a method for preparing the composition of the invention. The method is not especially limited, and any methods known in the art for blending or mixing such components may be employed, especially methods for blending and/or mixing powders. Thus, the method comprises mixing the first component with the second component to form the composition. In some embodiments, the first and second components are each, separately from each other, mixed with one or more excipients and/or additives before being mixed together to form the composition. In other embodiments, the components, additives, and/or excipients may be added sequentially to the mixture during the mixing process.

The selection of the excipients and the method of blending may be adapted in order to overcome any mixing, flow and fill issues or punch issues with the composition. The BioResponse DIM is provided in micro-encapsulated form, such that the powder particles have a tendency to clump together. In such circumstances the blending method is adapted to avoid creating hot spots of increased concentrations of the active ingredients. In addition, the composition is hydroscopic and light sensitive such that processing/blending times should be kept to a minimum, and in storage the powder should be protected from both light and air.

As additives and excipients, microcrystalline cellulose, magnesium silicate, tricalcium phosphate and magnesium stearate (a traditional lubricant) are preferred to help with flow characteristics and/or lubrication. However, other additives and excipients known in the art may be employed if desired. In some embodiments, it is desirable that the composition comprises 55-60% by weight of tricalcium phosphate.

The correct blending of all ingredients is important in achieving uniform capsule fills of the active ingredient. A V-blender is highly effective for successful mixing. Preferably, a minimum 316 grade stainless steel vessel is used for this process. Sieving is preferred at one or more of the start, the middle, and the end of the process. Blend studies to confirm blend uniformity should be completed to validate the method and formulation. Such methods and techniques are known in the art.

The invention also provides a second aspect, which comprises a composition for use in treating a skin condition, the composition comprising:

-   -   (a) a first component comprising a substituted or unsubstituted         diindolylmethane compound; and     -   (b) a second component different from the first component,         wherein the second component has a beneficial effect         supplementary to and/or complementary to the effect of the first         component,

wherein the second component is selected from an antibiotic compound, a substituted or unsubstituted azelaic acid compound, an oral contraceptive compound, sulphur, a sulphur-containing compound, a substituted or unsubstituted salicylic acid compound, a substituted or unsubstituted resorcinol compound, a plant product, a mineral, a vitamin, and a neutraceutical product.

In this second aspect, the antibiotic compound, substituted or unsubstituted azelaic acid compound, oral contraceptive compound, sulphur, sulphur-containing compound, substituted or unsubstituted salicylic acid compound, substituted or unsubstituted resorcinol compound, plant product, mineral, vitamin, and neutraceutical product may be any such compound or product as already described above in relation to the further component used in the first aspect of the invention. Accordingly, in the second aspect of the invention, the second component is not a retinoid compound, but is selected from the above compounds instead.

Any of the preferred features set out in the claims and description in relation to the first aspect of the invention may also apply to the second aspect of the invention. The methods, uses and kits of the first aspect are also applicable to the second aspect.

The invention will now be described in further detail by way of example only, with reference to the following specific embodiments.

EXAMPLES

Manufacture of Composition

Two different batches of DIM and vitamin A formulation were manufactured. The details of manufacture and formulation are set out below.

Formulation 1

1 capsule contains:

-   -   75 mg DIM (BioResponse LLC)     -   200 μg vitamin A palmitate retinol equivalents (366.4 μg retinyl         palmitate). This is equivalent to 2.666 mg of 250,000IU/g         vitamin A palmitate (BASF)     -   175 mg tricalcium phosphate     -   20 mg microcrystalline cellulose     -   10 mg vitamin C (ascorbic acid)     -   10 mg fumed silicon dioxide (or a fine particle precipitated         silica)     -   6 mg magnesium stearate

Blending Method for Formulation 1

Mixing was carried out in a sequential process according to the following protocol:

-   -   1. The DIM was sieved through a fine sieve and then mixed with         the magnesium stearate, half of the tricalcium phosphate and the         silicon dioxide for 10 mins in a V mixer. The mixed powder was         transferred into a food grade bag.     -   2. Separately, the vitamin C and retinyl palmitate were mixed         with the second half of the tricalcium phosphate and the         microcrystalline cellulose for 10 mins in a V mixer.     -   3. The mixed powders obtained from 1 and 2 were blended together         for 20 mins in a V mixer, then sieved, and mixed further for 1         hour and 10 minutes in a V mixer.     -   4. The blended powder was transferred to a suitable opaque and         air-tight container to ensure minimal contact with light and         oxygen.     -   5. A sample was taken from the top and bottom of the batch to         test for uniformity of mixing.

Formulation 2

1 capsule (297 mg) contains:

-   -   75 mg DIM (BioResponse LLC)     -   200 μg vitamin A palmitate retinol equivalents (366.4 μg retinyl         palmitate). This is equivalent to 1.333 mg of 500,000IU/g         vitamin A palmitate (BASF)     -   175 mg tricalcium phosphate     -   20 mg cellulose fibre     -   10 mg vitamin C (ascorbic acid)     -   10 mg silicon dioxide (Neosyl)     -   6 mg magnesium stearate

Blending Method for Formulation 2

-   -   1. The DIM was sieved thoroughly through a fine mesh into a         clean, sterile, plastic bag. The sieved DIM, the vitamin C, and         the retinyl palmitate were pre-mixed with the silicon dioxide         first in the sealed plastic bag for 5 minutes.     -   2. The tricalcium phosphate and microcrystalline cellulose were         then added to the premix and thoroughly mix for an additional 5         minutes. The resulting mixture was added to a V mixer and mixed         for 10 minutes.     -   3. The magnesium stearate was then added, and powder was mixed         for an additional 10 minutes.     -   4. the resulting mixed powder was removed and passed through a         fine grade sieve. It was then transfered back into the V mixer         and mixed for 30 minutes.     -   5. The resulting mixture was transfered to a suitable opaque and         air-tight container to ensure minimal contact with light and         oxygen.     -   6. A sample was taken from the top, centre, and bottom of the         batch to test for uniformity of mixing.

Encapsulation

The formulations referred to above may be encapsulated. The DIM is spray dried into particles of approximately 8 to 12 microns in diameter. The powder flow properties of particles at this size are very challenging. The powder, because of the specific ingredients that are used to achieve the bioavailability requirements, are somewhat cohesive. Because of this, certain types of encapsulation equipment can have difficulty with continued operation without stopping to clean punch faces or to adjust fill volumes.

DIM is known to be light sensitive. Therefore, opaque capsules are preferred, typically, size “0” capsules. Light resistant containers are preferred.

Patient Testing

The aim of this survey was to ascertain the efficacy of using oral DIM together with Vitamin A in order to treat Grade II to IV active acne. The results showed impressive improvements in the condition over a 3 month period with no side effects or worsening of the condition.

The survey was conducted using 2 trial groups, Group A and Group B. The composition employed comprised BioResponse DIM (75 mg per capsule) together with Solgar vitamin A (retinyl palmitate) (5,000IU per tablet).

Group A took between 150 mg and 300 mg DIM together with between 5,000IU and 10,000IU vitamin A daily. The results were measured using:

-   -   Visia skin analysis equipment     -   Photographs     -   Self-reporting: Group A rated their acne on a scale of 1 to 10         with 1 being good and 10 being bad before starting the         supplements and then again at the end of three months. The         results (marks out of 10 in percent) are shown in Table 1.

Group B took 300 mg DIM together with 2,500IU Vitamin A daily. The results were measured using:

-   -   Visia skin analysis equipment     -   Photographs     -   Self-reporting: At the beginning of the trial, the subjects         rated their acne on a scale of 1 to 10 with 1 being good and 10         being bad. Subsequently they were asked to rate their skin again         after 1, 2 and 3 months (end of the trial). A different rating         scale was used. This time the subjects were asked to rate their         acne on a scale between 1 and 6 with 1 being the best their skin         has been and 6 being the worst. The results (marks out of 10, or         out of 6 in percent) are shown in Table 2.

Results

TABLE 1 Group A self-scoring Patient No. 1 2 3 4 5 6 7 8 9 10 11 Before (%) 100 70 60 80 70 60 70 60 30 50 90 After (%) 30 40 24 35 10 40 70 40 10 0 20

The average score for Group A before treatment was 67%, whilst the average score after treatment was 29%, indicating a very large improvement. The photographs showing before and after conditions for patient 12 of group A are shown in FIG. 1 and FIG. 2 respectively.

TABLE 2 Group B self-scoring Patient No. 1 2 3 4 5 6 7 8 9 10 11 12 Before 50 60 100 70 50 90 60 50 80 70 70 80 After 3 m 50 50 17 83 33 50 17 33 83 83 17 33 (%)

The average score for Group B before treatment was 69%, whilst the average score after treatment was 46%, again indicating a very large improvement. The photographs showing before and after conditions for patient 11 of group B are shown in FIG. 3 and FIG. 4 respectively.

The results show that of the 23 patients who completed the study, 18 showed improvement in their condition (patients A7, B1, B4, B9, B10 showed no significant change in the condition). The average across the 18 was a 41% reduction, which represents a 59% improvement on the original score.

Evidence of the typical reduction in acne shown by patients treated with the agent of the invention is provided in FIGS. 1-4 in the form of ‘before and after’ photographs. The significant improvement is clearly visible.

These results demonstrate the significant potential of the proposed combined formulation in the treatment of acne and associated conditions, especially when DIM having improved bioavailability (as compared with pure DIM) is employed. 

1. A composition for use in treating a skin condition, the composition comprising: (a) a first component comprising a substituted or unsubstituted diindolylmethane compound; and (b) a second component comprising a substituted or unsubstituted retinoid compound.
 2. A composition according to claim 1, wherein the composition comprises a further component selected from one or more of: a further substituted or unsubstituted retinoid compound, an antibiotic compound, a substituted or unsubstituted azelaic acid compound, an oral contraceptive compound, sulphur, a sulphur-containing compound, a substituted or unsubstituted salicylic acid compound, a substituted or unsubstituted resorcinol compound, a plant product, a mineral, a vitamin, and a neutraceutical product.
 3. A composition according to claim 1, wherein the first component comprises a diindolylmethane compound having the following structure:

wherein the R groups may be the same or different and are selected from hydrogen atoms and C₁-C₆ hydrocarbon substituents; and wherein the indolyl groups are the same or different and may be indole-3-yl and/or indole-2-yl groups; and wherein the indolyl groups may be unsubstituted such that all substituents are hydrogen atoms, or may be substituted such that one or more substituents are selected from C₁-C₆ hydrocarbon substituents.
 4. A composition according to claim 3 wherein the first component comprises a substituted or unsubstituted 3,3′diindolylmethane compound and/or a substituted or unsubstituted 2,2′diindolylmethane compound selected from the following structures:

wherein the R groups may be the same or different and are selected from hydrogen atoms, or from C₁-C₆ hydrocarbon substituents.
 5. A composition according to claim 4 wherein the first component comprises a 3,3′diindolylmethane compound and/or a 2,2′diindolylmethane compound selected from the following structures:


6. A composition according to claim 1, wherein the retinoid compound is selected from a substituted or unsubstituted first generation retinoid, a substituted or unsubstituted second generation retinoid and a substituted or unsubstituted third generation retinoid.
 7. A composition according to claim 6, wherein the first generation retinoid is selected from a substituted or unsubstituted retinol, a substituted or unsubstituted retinal, a substituted or unsubstituted tretinoin (retinoic acid or Retin A), a substituted or unsubstituted isoretinoin, and a substituted or unsubstituted alitretinoin.
 8. A composition according to claim 6, wherein the first generation retinoid comprises vitamin A.
 9. A composition according to claim 6, wherein the second generation retinoid is selected from a substituted or unsubstituted etretinate, and a substituted or unsubstituted acitretin.
 10. A composition according to claim 6, wherein the third generation retinoid is selected from a substituted or unsubstituted tazarotene, a substituted or unsubstituted bexarotene, and a substituted or unsubstituted adapalene.
 11. A composition according to claim 2, wherein the antibiotic compound is suitable for oral and/or topical application and is selected from: tetracycline, oxytetracycline, minocycline, doxycycline, erythromycin and trimethoprim.
 12. A composition according to claim 2, wherein the azelaic acid compound comprises an antibacterial and/or an anti-inflammatory property.
 13. A composition according to claim 2, wherein the oral contraceptive comprises a female hormone and/or a compound with female hormone activity, capable of counteracting the effect of a male hormone.
 14. A composition according to claim 13, wherein the female hormone is oestrogen and the male hormone is testosterone.
 15. A composition according to claim 2, wherein the resorcinol compound comprises an antibacterial and/or an anti-inflammatory property.
 16. A composition according to claim 3, wherein an unsubstituted compound comprises only hydrogen atom substituents, and wherein a substituted compound comprises one or more C₁-C₆ hydrocarbon substituents.
 17. A composition according to claim 1, wherein the skin condition is selected from: acne, inflammation and aging.
 18. A composition according to claim 17, wherein the acne comprises acne vulgaris, seborrhoea, comedones, papules, pustules, nodules, cysts, boils and/or scarring.
 19. A composition according to claim 1 for oral or topical administration.
 20. A composition according to claim 19, in the form of a tablet, capsule, gel, cream or ointment.
 21. A pharmaceutical kit for separate, simultaneous or sequential administration for use in treating a skin condition, which kit comprises a first component and a second component, wherein the first and second components are as defined in claim
 1. 22. A composition or kit according to claim 1 or 21, wherein the diindolylmethane compound is synthetic, or is a natural product obtained from a Brassica plant.
 23. A composition or kit according to claim 21, wherein the diindolylmethane compound is adapted for increased bioavailability.
 24. A composition or kit according to claim 23, wherein the diindolylmethane compound comprises BioResponse Diindolylmethane (BioResponse LLC).
 25. A composition or kit according to claim 1 or 21, wherein the first component and/or the second component, and/or the further component comprises a further excipient and/or adjuvant.
 26. A composition or kit according to claim 25, wherein the first component comprises one or more further lipophilic compounds, preferably vitamin E and/or phosphatidylcholine.
 27. A composition or kit according to claim 1 or 21, wherein the first component is in a form suitable for providing a daily diindolylmethane dosage of 500 mg or less, preferably from 10-500 mg.
 28. A composition or kit according to claim 1 or 21, wherein the first component is for treating a skin condition in a daily dose of from 50-350 mg, preferably from 100-200 mg, preferably from 140-160 mg, preferably about 150 mg, or alternatively preferably from 250-350 mg, preferably from 290-310 mg or preferably about 300 mg.
 29. A composition or kit according to claim 27, wherein the first component is present in a dose which is a fraction of the daily dose, preferably a half of the daily dose, or a quarter of the daily dose, more preferably in an amount of 100-200 mg, 140-160 mg or about 150 mg, or alternatively in an amount of 50-100 mg, 70-80 mg, or about 75 mg, or alternatively from 15-100 mg, or from 18-75 mg.
 30. A composition or kit according to claim 1 or 21, wherein the second component is in a form suitable for providing a daily retinoid compound dosage of from 200-3000 μg.
 31. A composition or kit according to claim 1 or 21, wherein the daily dosage is provided in the form of one or more capsules or tablets, preferably in the form of 2 or 4 capsules or tablets.
 32. A method for treating a skin condition, which method comprises administering a composition or kit as defined in claim 1 or 21 to a subject.
 33. A method for preparing a composition of claim 1, which method comprises mixing the first component with the second component to form the composition.
 34. A method according to claim 33, wherein the first and second components are each, separately from each other, mixed with one or more excipients and/or additives before being mixed together to form the composition. 